Switch and outlet box



Dec. 16, 1930. J MlLCOFF -1,785,524

SWITCH AND OUTLET BOX Filed Dec. 27, 1928 embodiments of the invention.

Patented Dec. 16, 1930 UNITED STATES PATENT OFFICE JOSEPH E. MILCOFF, 0F LEETSIOALE, PENNSYLVANIA, ASSIGNOR- TO NATIONAL ELEC- TRIO PRODUCTS CORPORATION, OF NEW YORK, N. 'Y., A CORPORATION OF DELA WARE SWITCH AND OUTLET BOX This invention relates to switch and outlet boxes used for electrical purposes and especially to those boxes which are equipped with knock-outs and which are provided with interior parts such as clamps and bushings which are disposed within the boxes and which-parts," on account of their disposition, make it difiicult to remove knock-out parts which are disposed behind such bushings or plates. I

This invention has for its object the pro vision of a simple arrangement which will permit the easy removal of knock-outs irrespective of their disposition in the boxes and irrespective of such knock-out being disposed back of bushing plates or members.

A further object of the present invention resides in the provision of a construction which will afford afulcrumfor an inserted implement and therebyfacilitate the prying out of a knock-out or'k-nock-outs from the boxes.

Other objects and advantages will be hereinafter set forth in the accompanying specification and claims and shown in the drawings,

which by way of illustration show preferred In the drawings Figure 1 is a top plan view of a conventional switch, or outlet box embodying my improvements Fig.-'2 is an end view of the boxshown in Fig. ,1 looking from the right;

Fig. 3 is a sectional view' taken on lines 33 of Fig. 1 and shows the manner of prying out a knock-out with an inserted implement.

such as ascrew driver; f

Fig. 4 is a detail endview of the box similar to Fig. 2 but with a clamping member disposed in the box for clamping the cables therein;

Fig. 5 is asectional view taken on lines 55 of Fig. 1' and shows the clamp in cooperation with the cable;

Fig. 6 is a detail view showing a different manner of securing the shelf in position.

In more detail, 10 is a sheet metal box provided with knock-out portions 11. A supplemental interior member 12 is provided secured within the box in any desired way as by the bent over clipped ends 13. This member 12 is provided with bushed openings 14 which are disposed opposite knock-outs 11 which are at the end of the box as shown in Fig. 2. Member 12 is also provided with openings 15 (see Fig. 1), which openings 15 are directly above the centre of the knock-outs 11 which are disposed in' the end Wall of the box. With the shelf-like member or bushing plate 12 in position and when it is desired to remove a knock-out or knock-outs, it is simply necessary to insert. a screw driver or like implement 16 through the openings 15 and then pry back on such implement. The back edge of the opening 15 serves to afi'ord a ful crumfor such implement and the knock-out can be readily pried out from theibox wall.-

According to the construction shown in Figs. 4 and 5, the member 12, which maybe I termed a bushing plate, is drilled to receive a screw 17 adapted to engage an L-shaped clamping piece 18. By turning up the screw the L-shaped clamping piece 18 may be drawn upwardly to engage and clamp theinserted cable.

cables thereby that there is noobstructi'onor hindrance to the removal of a knock-out or knock-outs.

The box can be completely assembled with the bushing plate and the clamping parts in assembled relation and subsequentlyd'esired knock-outs can be pried out by the use of the im lement.- Preferably,- the disposition of the openings 15 in the bushing plate is substantially at the center line of the knock-outs.

In Fi 6 a screw 13a is employed instead of one 0% the turn over clips 13. v

It will be understood that bushingplates or members such as 12 can be placed'opposite any of the knock-outs of the box and secured in position therein. This is the conventional practice with such outlet or switch box construction. Irrespective of the disposition of such bushing plate or member 12 the openings 15 will be provided in such plate and in such position as to afford access to the knock-outsand to thereby facilitate the removal of the same after the bushing plate has been assembled and secured in position in the box.

. I claim:

1. An outlet box having knock-outs and provided with a rigid inflexible bushing plate within the box, said bushing plate being pro-' vided with supplemental openings disposed at points substantially above the center of the knock-outs to permit an implement to be inserted therethrough and fulcrumed upon the rigid inflexible bushing plate for the purpose described.

2. An outlet box provided with knock-outs and having therein a bushing plate which is secured to the said box, said bushing plate being rigid and inflexible and being pro vided with an opening'and having an edge thereof so disposed that an implement may be inserted through the opening and ful- 2o crumed upon such edge of the rigid bushing plate to pry out a knock-out from thebox.

3. An outlet box provided with knock-out elements and also provided with a rigid inflexible bushing plate disposed within the box and secured thereto, said bushing plate having openings adjacent the edge of the box and in proximity to the knock-out elements to provide for the reception of an implement which can fulcrum against the rigid inflexible bushing plate and upon the ed e of the opening away from the wall of the ox andalso bear nature.

JOSEPH E. MILCOFF.

upon a knock-out to pry the latter from the box.

4. An outlet box having a rigid bushing plate secured therein and having a knock-out portion in the wall of the box, said bushing plate. having an opening to receive an implevment which can bear upon the inside of a knock-out and also bear upon an edge of the opening in the rigid plate so that the implement may be fulcrumed about such edgeto pry out said knock-out.

5. An outlet box provided with knock-out elements and also provided with a rigid bushing plate disposed within the box and secured thereto, and a clamping means for clamping the cable into cooperation with the bushin plate and having means associated therewlth and with the bushing plate for drawin up the clamping means into cooperation with cables inserted through knock-out openings, said bushing plate having openings adjacent the edge of the box and in proximity to the knock-out elements to provide for the reception of an implement which is fulcrumed upon the edge of the openin in the rigid plate away from the wall of the ox and also bears upon a knock-out to pry the latter out from the box, and said clamping means being normally disposed in such position as not to obstruct entrance of the prying out implement through the openings in the bushing plate.

6. An outlet box having knock-out por- 65 tions therein and a rigid part carried by and 

